D’Amico logs his daily meals on his blog, and is currently on Day 21 of the challenge. Despite his doctor's warnings, he told the Sun-Times he has been feeling good.

"From day one, I received such positive feedback and encouragement from friends, family and even those I never met," D’Amico said on his fundraising page. "That made me realize that I could provide more than just a little entertainment and inspiration; I could actually make a difference!"

D’Amico, who runs a 6 minute mile and logs more than 100 miles per week, told WGN Radio Thursday that he is not being paid by McDonald's, and not trying to make a political statement.

"I'm a free agent," he told the station. "I pay for all my McNuggets and all my shoes. I'm just a regular guy trying to run fast."

"I'm rolling along and feeling quite good," D’Amico told WGN, adding that he never counts calories. "..It helps to run that many miles, you can eat a little bit more liberally."

An average McDonald's meal day for D’Amico includes an Egg McMuffin without Canadian bacon, a grilled chicken sandwich without the mayo, a hamburger and some cookies.

To track the McRunner's progress (and help him raise money for charity), follow him on Twitter and Facebook. To help D'Amico raise money for the Ronald McDonald House Charities of Chicagoland and Northwest Indiana, go here.